mirror of
https://github.com/RevCurtisP/C02.git
synced 2024-11-28 10:51:14 +00:00
57 lines
1.5 KiB
Plaintext
57 lines
1.5 KiB
Plaintext
;Screen Control Assembly Lanuage Routines for Oric-1
|
|
|
|
SUBROUTINE _SCREEN
|
|
|
|
SMTEXT EQU $00 ;Default Text Screen
|
|
SMWIDE EQU $FF ;Wide Text Screen (Undefined)
|
|
|
|
;Set Screen Mode
|
|
SETSCR: CMP SMTEXT ;If Default Text Screen
|
|
BEQ GETSCR ;Return Return 0
|
|
LDA #$FF ;Else Return ERROR
|
|
RTS
|
|
;Else Return 0
|
|
;Get Screen Mode
|
|
GETSCR: LDA #0 ;Return 0 (Default Text Mode)
|
|
RTS
|
|
|
|
;Clear the Screen
|
|
CLRSCR EQU $CC0A ;Basic CLS Routine (Atmos = $CCCE)
|
|
|
|
;Move Cursor to Home Position
|
|
CRSRHM: LDA #0 ;Set Args to 0,0
|
|
TAY ;and Fall into SETPOS
|
|
|
|
;Set Cursor Position
|
|
SETPOS: CLC
|
|
ADC #2 ;Add 2 to Column
|
|
PHA ;and Save It
|
|
INY ;Add 1 to Row
|
|
TYA ;and Save It
|
|
PHA
|
|
LDA #0 ;Turn Cursor Off
|
|
JSR $F7CB
|
|
PLA ;Retrieve Row
|
|
STA $0268 ;and Store in CURROW
|
|
PLA ;Retrieve Column
|
|
STA $0269 ;and Store in CURCOL
|
|
JSR $F67D ;Recalculate Screen Pointers
|
|
LDA #0 ;Turn Cursor On
|
|
JMP $F7CB ;and Return
|
|
|
|
;Get Cursor Position
|
|
GETPOS: LDA $0269 ;Load Column from CURCOL
|
|
SEC
|
|
SBC #2 ;Subtract 2
|
|
BPL GETPOY ;If Negative
|
|
LDA #0 ;set to 0
|
|
GETPOY: LDY $0268 ;Load Row from CURROW
|
|
DEY ;and Subtract 1
|
|
RTS
|
|
|
|
;Get Screen Size
|
|
GETSIZ: LDA #38 ;38 Columns (First 2 are Protected)
|
|
LDY #27 ;27 Rows
|
|
RTS
|
|
|